[halvenut]

Before I altered anything I'd shoot 100 rounds through the gun.
Often odd problems go away with a little break in.
If the stop is still too hard to install or remove, then alter the stop slightly.

Also you can push back on the plunger pin as long as you're carefull not to scratch the slide, use something plastic if possible. Often times after you fire it some the slide stop will pop right in.